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FEATURES
Monolithic
12-Bit 20 MSPS A/D Converter
Low Power Dissipation: 1.4 Watts
On-Chip T/H and Reference
High Spurious-Free Dynamic Range
TTL Logic
APPLICATIONS
Radar Receivers
Digital Communications
Digital Instrumentation
Electro-Optics
FUNCTIONAL BLOCK DIAGRAM
ANALOG
INPUT
T/H
5-BIT
ADC
DIGITAL
12
ERROR
CORRECTION TTL
5-BIT
ADC
DAC
ENCODE
T/H
OBS
PRODUCT DESCRIPTION
12-Bit 20 MSPS
Monolithic A/D Converter
AD9022
+2V
REF
16
DAC
8
4-BIT
ADC
+5V
–5.2V
GND
OLE
The AD9022 is a high speed, high performance, monolithic 12bit analog-to-digital converter. All necessary functions, including track-and-hold (T/H) and reference, are included on chip to
provide a complete conversion solution. It is a companion unit
to the AD9023; the primary difference between the two is that
all logic for the AD9022 is TTL compatible, while the AD9023
utilizes ECL logic for digital inputs and outputs. Pinouts for the
two parts are nearly identical.
Operating from +5 V and –5.2 V supplies, the AD9022 provides excellent dynamic performance. Sampling at 20 Msps with
AIN = 1 MHz, the spurious-free dynamic range (SFDR) is typically 76 dB; with AIN = 9.6 MHz, SFDR is 74 dB. SNR is typically 65 dB.
The on-board T/H has a 110 MHz bandwidth and, more importantly, is designed to provide excellent dynamic performance for
analog input frequencies above Nyquist. This feature is necessary in many under-sampling signal processing applications,
such as in direct IF-to-digital conversion.
With DNL typically less than 0.5 LSB and 20 ns transient response settling time, the AD9022 provides excellent results
when low-frequency analog inputs must be oversampled (such
as CCD digitization). The full scale analog input is ± 1 V with a
300 Ω input impedance. The analog input can be driven directly
from the signal source, or can be buffered by the AD96xx series
of low noise, low distortion buffer amplifiers.
TE
All timing is internal to the AD9022; the clock signal initiates
the conversion cycle. For best results, the encode command
should contain as little jitter as possible. High speed layout practices must be followed to ensure optimum A/D performance.
The AD9022 is built on a trench isolated bipolar process and
utilizes an innovative multipass architecture (see the block
diagram). The unit is packaged in 28-pin ceramic DIPs and
gullwing surface mount packages. The AD9022 is specified to
operate over the industrial (–25°C to +85°C) and military
(–55°C to +125°C) temperature ranges.
To maintain dynamic performance at higher IFs, monolithic
RF track-and-holds (such as the AD9100 and AD9101
Samplifier™) can be used with the AD9022 to process signals
up to and beyond 70 MHz.
Samplifier is a trademark of Analog Devices, Inc.
REV. A
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood. MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
